Conventionally, a gear shift unit for finger touch control is known wherein a driver manually operates a gear shift lever. A transmission signal obtained therefrom is processed by a control box so as to supply a predetermined operation signal to the gear shift unit, and the unit switches a transmission using a booster driven by a pneumatic pressure. A gear shift unit of this type is disclosed in specifications and drawings of Japanese Utility Model Application Nos. 57-144735 and 57-138832. Such an apparatus can reduce fatigue of the driver since force to operate the transmission can be decreased. However, the clutch must be engaged/disengaged by the driver in the case of a transmission switching operation.